/*--------------------------------------------------------------
TEMPLATE FILE FOR DEFINING THALAMOCORTICAL NEURONS
SIMPLIFIED VERSION BY GH Dec. 2011
--------------------------------------------------
One compartment model and currents derived from:
McCormick, D.A. and Huguenard, J.R. A model of the
electrophysiological properties of thalamocortical relay neurons.
J. Neurophysiology 68: 1384-1400, 1992.
- passive: parameters idem Rinzel
- HH: Traub with higher threshold
- IT: m2h, nernst, tau_h modified with double exponential
- Ih: Huguenard with Ca++ dependence added, Ca++-binding protein
- Ca++: simple decay, faster than McCormick
This model is described in detail in:
Destexhe, A., Bal, T., McCormick, D.A. and Sejnowski, T.J.
Ionic mechanisms underlying synchronized oscillations and propagating
waves in a model of ferret thalamic slices. Journal of Neurophysiology
76: 2049-2070, 1996.
See also http://www.cnl.salk.edu/~alain , http://cns.fmed.ulaval.ca
Alain Destexhe, Salk Institute and Laval University, 1995
--------------------------------------------------------------*/
begintemplate sTC // create a new template object
public soma, all //, kl
objref all
create soma[1] // one compartment of about 7000 um2
soma {
nseg = 1
diam = 47
L = 47
cm = 1
}
//objectvar kl
proc init() { local v_potassium, v_sodium
//objectvar kl
//kl = new kleak()
v_potassium = -100 // potassium reversal potential
v_sodium = 50 // sodium reversal potential
soma {
diam = 47 // geometry
L = 35 //47 // so that area is about 7000 um2
nseg = 1
Ra = 100
insert pas // leak current
e_pas = -63 // gives rest = -60mV and tonic mode
g_pas = 3.8e-5 // from Rhodes & Llinas 2005
// kl.loc(0.5) // K-leak
// Erev_kleak = v_potassium
// kl.gmax = 0.004 // (uS)
// conversion: x(uS) = x(mS/cm2)*29000e-8*1e3
// = x(mS/cm2) * 0.29
/*
insert iar // h-current
eh = -40 // reversal
nca_iar = 4 // nb of binding sites for Ca++ on protein
k2_iar = 0.0004 // decay of Ca++ binding on protein
cac_iar = 0.002 // half-activation of Ca++ binding
nexp_iar = 1 // nb of binding sites on Ih channel
k4_iar = 0.001 // decay of protein binding on Ih channel
Pc_iar = 0.01 // half-activation of binding on Ih channel
ginc_iar = 2 // augm of conductance of bound Ih
ghbar_iar = 2e-5 // low Ih for slow oscillations
*/
insert TChh2 // Hodgin-Huxley INa and IK
ek = v_potassium
ena = v_sodium
// vtraub_TChh2 = -25 // High threshold to simulated IA
vtraub_TChh2 = -50 // Typical AP-spiking threshold.
// gnabar_TChh2 = 0.09 //
gnabar_TChh2 = 0.015
// gkbar_TChh2 = 0.01
gkbar_TChh2 = 0.0025
insert TCit // T-current
cai = 2.4e-4
cao = 2
eca = 120
// gcabar_TCit = 0.002
gcabar_TCit = 0.0002 // Destexhe values are too extreme.
insert TCcad // calcium decay
depth_TCcad = 1
taur_TCcad = 5
cainf_TCcad = 2.4e-4
kt_TCcad = 0 // no pump
}
all = new SectionList()
soma all.append()
}
endtemplate sTC